Add websocket::stream pong and async_pong

CHANGELOG.md

@@ -11,6 +11,7 @@ WebSocket
 
 * Write buffer option does not change capacity
 * Close connection during async_read on close frame
+* Add pong, async pong to stream
 
 Core
 

doc/websocket.qbk

@@ -329,7 +329,7 @@ Ping and pong messages are control frames which may be sent at any time
 by either peer on an established WebSocket connection. They are sent
 using the functions
     [link beast.ref.websocket__stream.ping `ping`] and
-    [link beast.ref.websocket__stream.ping `pong`].
+    [link beast.ref.websocket__stream.pong `pong`].
 
 To receive pong control frames, callers may register a "pong callback" using
 [link beast.ref.websocket__stream.set_option `set_option`]. The object provided

include/beast/websocket/detail/stream_base.hpp

@@ -104,7 +104,6 @@ protected:
         // The write buffer.
         // The buffer is allocated or reallocated at the beginning of
         // sending a message.
-        //
         std::unique_ptr<std::uint8_t[]> buf;
 
         void

include/beast/websocket/impl/ping.ipp

@@ -38,7 +38,7 @@ class stream<NextLayer>::ping_op
 
         template<class DeducedHandler>
         data(DeducedHandler&& h_, stream<NextLayer>& ws_,
-                ping_data const& payload)
+                opcode op_, ping_data const& payload)
             : ws(ws_)
             , h(std::forward<DeducedHandler>(h_))
             , cont(boost_asio_handler_cont_helpers::
@@ -46,8 +46,8 @@ class stream<NextLayer>::ping_op
         {
             using boost::asio::buffer;
             using boost::asio::buffer_copy;
-            ws.template write_ping<static_streambuf>(
+            ws.template write_ping<
-                fb, opcode::ping, payload);
+                static_streambuf>(fb, op_, payload);
         }
     };
 
@@ -191,19 +191,38 @@ upcall:
 }
 
 template<class NextLayer>
-template<class PingHandler>
+template<class WriteHandler>
 typename async_completion<
-    PingHandler, void(error_code)>::result_type
+    WriteHandler, void(error_code)>::result_type
 stream<NextLayer>::
-async_ping(ping_data const& payload, PingHandler&& handler)
+async_ping(ping_data const& payload, WriteHandler&& handler)
 {
     static_assert(is_AsyncStream<next_layer_type>::value,
         "AsyncStream requirements requirements not met");
     beast::async_completion<
-        PingHandler, void(error_code)
+        WriteHandler, void(error_code)
             > completion(handler);
     ping_op<decltype(completion.handler)>{
-        completion.handler, *this, payload};
+        completion.handler, *this,
+            opcode::ping, payload};
+    return completion.result.get();
+}
+
+template<class NextLayer>
+template<class WriteHandler>
+typename async_completion<
+    WriteHandler, void(error_code)>::result_type
+stream<NextLayer>::
+async_pong(ping_data const& payload, WriteHandler&& handler)
+{
+    static_assert(is_AsyncStream<next_layer_type>::value,
+        "AsyncStream requirements requirements not met");
+    beast::async_completion<
+        WriteHandler, void(error_code)
+            > completion(handler);
+    ping_op<decltype(completion.handler)>{
+        completion.handler, *this,
+            opcode::pong, payload};
     return completion.result.get();
 }
 
@@ -229,6 +248,28 @@ ping(ping_data const& payload, error_code& ec)
     boost::asio::write(stream_, db.data(), ec);
 }
 
+template<class NextLayer>
+void
+stream<NextLayer>::
+pong(ping_data const& payload)
+{
+    error_code ec;
+    pong(payload, ec);
+    if(ec)
+        throw system_error{ec};
+}
+
+template<class NextLayer>
+void
+stream<NextLayer>::
+pong(ping_data const& payload, error_code& ec)
+{
+    detail::frame_streambuf db;
+    write_ping<static_streambuf>(
+        db, opcode::pong, payload);
+    boost::asio::write(stream_, db.data(), ec);
+}
+
 //------------------------------------------------------------------------------
 
 } // websocket

include/beast/websocket/impl/write.ipp

@@ -40,7 +40,7 @@ namespace websocket {
         system call, by concatenating the frame header and the payload.
 
         In the client role, this will send a single frame in one system
-        calls, using the write buffer to calculate masked data.
+        call, using the write buffer to calculate masked data.
 
     2.  autofragment: true
         compression:  false

include/beast/websocket/stream.hpp

@@ -987,14 +987,107 @@ public:
         this function. Invocation of the handler will be performed in a
         manner equivalent to using `boost::asio::io_service::post`.
     */
-    template<class PingHandler>
+    template<class WriteHandler>
 #if GENERATING_DOCS
     void_or_deduced
 #else
     typename async_completion<
-        PingHandler, void(error_code)>::result_type
+        WriteHandler, void(error_code)>::result_type
 #endif
-    async_ping(ping_data const& payload, PingHandler&& handler);
+    async_ping(ping_data const& payload, WriteHandler&& handler);
+
+    /** Send a WebSocket pong frame.
+
+        This function is used to synchronously send a pong frame on
+        the stream. The call blocks until one of the following is true:
+
+        @li The pong frame finishes sending.
+
+        @li An error occurs on the stream.
+
+        This function is implemented in terms of one or more calls to the
+        next layer's `write_some` functions.
+
+        The WebSocket protocol allows pong frames to be sent from either
+        end at any time. It is not necessary to first receive a ping in
+        order to send a pong. The remote peer may use the receipt of a
+        pong frame as an indication that the connection is not dead.
+
+        @param payload The payload of the pong message, which may be empty.
+
+        @throws system_error Thrown on failure.
+    */
+    void
+    pong(ping_data const& payload);
+
+    /** Send a WebSocket pong frame.
+
+        This function is used to synchronously send a pong frame on
+        the stream. The call blocks until one of the following is true:
+
+        @li The pong frame finishes sending.
+
+        @li An error occurs on the stream.
+
+        This function is implemented in terms of one or more calls to the
+        next layer's `write_some` functions.
+
+        The WebSocket protocol allows pong frames to be sent from either
+        end at any time. It is not necessary to first receive a ping in
+        order to send a pong. The remote peer may use the receipt of a
+        pong frame as an indication that the connection is not dead.
+
+        @param payload The payload of the pong message, which may be empty.
+
+        @param ec Set to indicate what error occurred, if any.
+    */
+    void
+    pong(ping_data const& payload, error_code& ec);
+
+    /** Start an asynchronous operation to send a WebSocket pong frame.
+
+        This function is used to asynchronously send a pong frame to
+        the stream. The function call always returns immediately. The
+        asynchronous operation will continue until one of the following
+        is true:
+
+        @li The entire pong frame is sent.
+
+        @li An error occurs on the stream.
+
+        This operation is implemented in terms of one or more calls to the
+        next layer's `async_write_some` functions, and is known as a
+        <em>composed operation</em>. The program must ensure that the
+        stream performs no other writes until this operation completes.
+
+        The WebSocket protocol allows pong frames to be sent from either
+        end at any time. It is not necessary to first receive a ping in
+        order to send a pong. The remote peer may use the receipt of a
+        pong frame as an indication that the connection is not dead.
+
+        @param payload The payload of the pong message, which may be empty.
+
+        @param handler The handler to be called when the read operation
+        completes. Copies will be made of the handler as required. The
+        function signature of the handler must be:
+        @code
+        void handler(
+            error_code const& error     // Result of operation
+        );
+        @endcode
+        Regardless of whether the asynchronous operation completes
+        immediately or not, the handler will not be invoked from within
+        this function. Invocation of the handler will be performed in a
+        manner equivalent to using `boost::asio::io_service::post`.
+    */
+    template<class WriteHandler>
+#if GENERATING_DOCS
+    void_or_deduced
+#else
+    typename async_completion<
+        WriteHandler, void(error_code)>::result_type
+#endif
+    async_pong(ping_data const& payload, WriteHandler&& handler);
 
     /** Read a message from the stream.
 

test/websocket/stream.cpp

@@ -910,6 +910,9 @@ public:
                 }
                 ws.set_option(pong_callback{});
 
+                // send pong
+                ws.pong("");
+
                 // send auto fragmented message
                 ws.set_option(auto_fragment{true});
                 ws.set_option(write_buffer_size{8});
@@ -1172,6 +1175,9 @@ public:
                     ws.set_option(pong_callback{});
                 }
 
+                // send pong
+                ws.async_pong("", do_yield[ec]);
+
                 // send auto fragmented message
                 ws.set_option(auto_fragment{true});
                 ws.set_option(write_buffer_size{8});